Triple valte foe air brakes



4 Sheets-Sheet I.

(No Model.)

. H. L. HOWE. TRIPLE .VALVE FOR AIR BRAKES.

Patented-Oct. 24, 1893-. Q

sakuwok (No Model.) 4 Sheets-Sheet 2.

H. L. HOWE. TRIPLE VALVE FOR AIR BRAKES.

No. 507,132. Patented Oct. 24, 1893.

' ATTORNEY (No Mbdel.) f

' H. L. HOWE. A

TRIPLE VALVE FOR AIR BRAKES.

Patented Oct. 24, 1 893.

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ZMM o w M 41% 4 Sheets-Sheet 3.

(No ModeL) 4 Sheets-Sheet 4.

H. L. HOWE.

TRIPLE VALVE FOR AIR BRAKES.

.To Brake, @Zindcr s 9 W. 4, .2 t 5 m l m W 22mg. figyfi w M A a H h w aF E. h f I J. a 2 2 B 7 0 5 DWI 07 WWW $16 NITED STATES PATENT QFFICE.

HENRY L. HOWE, or CANANDAIGUA, NEW YORK.

TRIPLE VALVE FOR AIR-BRAKES.

SPECIFICATION forming part of Letters Patent No. 507,132, dated October24, 1893.

Serial No. 435,735. (No model.)

T0 at whom it may concern.-

Be it known that I, HENRY L. HOWE, a citizen of the United States ofAmerica, residing at Oanandaigua, in the county of Ontario and State ofNew York, have invented certain new and useful Improvements in TripleValves for Air-Brakes, of which the following is a specification.

This invention relates generally to that class of valves now commonlyknown as triplevalves for air brakes, that is to say, avalve capable ofcontrolling three different air passage connections, as for instance thecon nection between a supply or train-pipe and an auxiliary reservoir,between an auxiliary reservoir and an operating or brake cylinder, and adirect connection between the supply or train-pipe and the operating orbrake-cylinder.

In the triple valves now in common use there is providedaby pass orcharging slot around the operating piston by which the fluid pressuremay leak around or past said piston from the train pipe into theauxiliary reservoir after the train pipe pressure has been raised and iseffecting the release of the brakes and also by which a leakage aroundor past said piston is had from the auxiliary reservoir into the trainpipe when the train pipe pressure is first reduced to effect theapplication of the brakes. In one of these instances there is anunnecessary leakage of air from the auxiliary reservoir into thetrainpipe and in the other from the train pipe into the auxiliaryreservoir, which tends to interfere with the timely response of theoperating parts to any change in pressure in the train pipe. In otherwords, the effectiveness of the change of pressure in the train pipe,either to apply the brakes or to let them off, is lessened in proportionto the quantity of air that leaks or is permitted to leak around theoperating piston.

In the old forms of valves in bringing the parts to release position,the train pipe pressure has to feed as many auxiliary reservoirs asthere are cars, and hence, where there are a number of cars the triplevalves nearest the engine will operate earlier than those fartherremoved so that the engineer is required to keep supplying such pressurein the train pipe to overcome the leakages in the succeeding triplevalves, as they operate successively and uncover the charging slots tocharge the auxiliary reservoirs. The present invention primarily, isdirected to wholly overcome this permissive leakage, .so thatimmediately a change of pressure is made in the train pipe that changeeffects the desired result of itself, and the entire variation in trainpipe pressure is utilized to accomplish the movement of the triple valvewithout such change in pressure being reduced in effectiveness by beingaugmented or lessened. To this end, also, only that variation ofpressure in the train pipe need be made which is absolutely necessary toproduce the desired movement of the parts, thereby lessening the extentof variation needed, and also making the parts respond immediately andwithout the delay which necessarily occurs when there is a leakage ofthe pressure from one part of the valve to another.

' Having these objects in view my improvements consist essentially in ameans by which the pressure is retained in the supply or train pipeuntil a certain reduction of pressure has been effected in the brakecylinder, or until the triple valve has been moved to its releaseposition whereby such train pipe pressure thus prevented from leakinginto the auxiliary reservoir, is brought to bear wholly upon theoperating piston to cause its movement quickly and without any loss ofair, or of pressure. These means also enable all the triple valves in along train of cars to move to release position substantiallysimultaneously instead of successively because the effective pressure inthe train pipe throughout the length of a train is operating withoutleakage upon the operating piston of each of the triple valves and suchpressure is retained in the train pipe, can be quickly raised inpressure, and such pressure maintained, and confined to effect themovement of the operating piston without losing any of its effectivenessby reason of any portion of the quantity or pressure of the airexpanding into the auxiliary reservoir. These means also operate toeifect the proper and quick application of the brakes when the trainpipe pressure is reduced and to lessen the amount of reduction needed byclosing all communication between the auxiliary reservoir and the trainpipe so that the m, l 1. l

auxiliary reservoir pressure is saved for use in putting on the brakesand is prevented from leaking into the train pipe to retard thereduction of pressure in the train pipe as well as to lessen thepressure in the auxiliary reservoir. The improved means, therefore,compels an immediate response on the part of the movable parts of thetriple valve upon any change of pressure in the train pipe so that thebrakes are quickly applied and quickly released, no matter what thelength of the train of cars may be; by which much air is saved inproducing the desired movements of the triple valve, and a less changein quantity of fluid supplied to or exhausted from the train pipe isneeded to produce such movement.

In another application filed by me in the United States Patent Office,February 6, 1892, Serial No. 420,496, there is shown and set forth anovel construction and arrangement of cooperating slide-valves, and apiston, with proper ports and passages, by which the triplevalve actionis effected by variation of the pressure in the train pipe, and thepresent improvements are for convenience shown and described herein inconnection with such a form of triple valve as a practicalexemplification of the same. The particularimprovement, it is to beunderstood, is not intended thereby to be limited in its use to suchaform of valve.

Briefly stated, the improvements consist in a valve, piston or the likeadapted to automatically control a passage or bypass between i thesupply or train pipe and an auxiliary reservoir, said valve beingcontrolled in its position by a certain difference in pressure betweenthat in said supply or train pipe and that in the operating or brakecylinder, whereby, first, upon a reduction in pressure in the train pipeand an accumulation of pressure in the brake cylinder, the communicationthrough the aforesaid passage between the train pipe and auxiliaryreservoir is cut oflt'; second, the pressure in the brake cylinder maybe reduced before this communication between the train pipe andauxiliary reservoir is opened to recharge said reservoir; and third, thetrain pipe pressure is retained until the triple valve is brought toarelease position or to a position to relieve or exhaust the pressure inthe brake-cylinder, thereby'preventing all loss of pressure in the trainpipe through premature leakage therefrom into the charging ports of thetriple valve or connected devices, and holding the pressure on the fluidin the train pipe until the pressure in the brake cylinder has beenreduced by exhausting it down to a low degree, and thereby effecting apositive release of the brakes.

The accompanying drawings illustrate a practical embodiment of theinvention in one form of triple valve for air brakes.

In said drawings: Fign re 1, is a vertical sectional elevation of atriple valve provided with the improvement, the parts being shown in theexhaust or running position. Fig. 2, is a similar view, showing theparts in servicestop position; and Fig. 3, isa like view with the partsin emergency-stop position. Fig. 4, is a sectional elevation of anotherform of valve with the present improvements added.

As the general construction and arrangement of the triple valve are thesame as that set forth in my said application, corresponding parts willbe lettered and numbered and called alike.

The valve shell 1, is provided with avalve chamber 2, having an openingfor communication with an auxiliary reservoir; ducts 3, 3 communicatingwith a brake cylinder opening 3; a passage 5 leading to thetrainpipe-opening 4, being also open to the pistoncylinder 6 throughpassage 14; and having a passage in communication with the exhaust port7. In the valve chamber 2 are arranged a pair of slide valves 8 and 10;the valve 8 is a recessed valve and controls the ducts 3, 3", thepassage to the exhaust port 7, and the passage 5 to the train pipe, andhas an independ ent exhaust duct 9 extending across its recess which atthe proper time coincides with the passage to the exhaust port 7; and italso has an opening 8 through its top wall. The valve 8 is also providedwith a flange 8, that is adapted to overlie and partially close thetrain pipe passage 5 so that the passage from the train pipe passageinto the valve chamber 2 is somewhat restricted during the ordinaryoperation of the triple valve, but in emergency stop position, when thevalve 8 has been moved as hereinafter set forth, the passage 5 iscompletely opened to the recess of the valve 8. The other valve 10partially contains or overlies the valve 8 and moves the latter throughits projections 11, 12, a sufficient space being provided between saidprojections and the valve 8 to permit a limited movementof the valve 10relative to the other valve. The valve 10 has an inner recess 10 adaptedto open communication between the chamber of the valve 8 and the exhaustport 7 through opening 8 and duct 9; and also a port l0 that coincideswith a port 8 in the valve 8 at the proper time.

The pair of valves 8, 10, are moved by connection with an operatingpiston 15, arranged in the cylinder 6 through a stem 16 leading from thevalve 10. The movement of the piston 15 and pair of valves in onedirection is yieldingly opposed by a suitable spring 17, arranged in arecess 20 in the head 19 of the valve shell 1, its pressure beingregulated and held by an adjusting screw 21 and lock nut 23. The spring,however, is of such length as to allow the piston 15 and its immediatelyconnected valve 10 to move a short distance from their limit of movementin one direction unopposed by said spring, as will be observed byreferring to Fig.1.

The passage 5 to the train pipe is provided with a double seated checkvalve 13 working in an enlargement 5 between upper and lower valve seats13 and 13% the wings of the valve fitting and being guided by the wallsof the passage 5. The passage 5 is constantly in communication by anannular channel 14 and piston duct 14, with the piston cylinder 6 inrear of the operating piston 15, the piston not acting to restrict orcutoff such communication.

The piston 15 is provided with an arm 18, extending forward across thepassage 5, and over the double check valve 13, adapted to engage with aprojection 18 on the end of the check valve when the piston is at thelimit of its rearward or emergency stroke to hold said check valve fromseating against its upper seat 13 when the parts are in emergencyposition, as in Fig.3, so that the brake cylinder may receive the fluiddirect from the train pipe in addition to that from the auxiliaryreservoir, and when said arm 18 is moved slightly from this stoppingposition permitting said valve to close against its upper seat 13-immediately the train pipe pressure is raised to cause the piston andvalves to move toward the release position asin Fig. 1. This closing ofthe double check-valve 13 against its upper seat 13 and shutting off thefurther passage of fluid to brake cylinder the instant it is desired torelease the brakes in a long train of cars, is obviously of greatimportance, as thereby the letting off of the brakes is not retarded bythe passing of the fluid from the train pipe to the auxiliary reservoiror to the brake cylinder, and hence very little fluid is wasted from thetrain pipe in effecting the release of the brakes, which fluid may,therefore, be stored up and maintained in the train pipe until such timeas the by passage hereinafter described will have opened communicationbetween the train pipe passage and the auxiliary reservoir when thefluid can then be let into said reservoir.

As the double check valve 13 will seat itself against its upper seat 13when free from the arm 18, immediately the train pipe pressure israised, means must be provided to open communication between the trainpipe and the auxiliary reservoir, around, or past, as it were, saidcheck valve; and these means should be subject to the control of thefluid pressure or the difference in pressures in the apparatus so as toact automatically, that is to say, should close communication betweenthe train pipe and the auxiliary reservoir, and then open communicationwith said reservoir only after the triple valve has moved to releaseposition. This automatic control is efiected in the present instance byproviding a differential piston controlling said communication andexposed at one side or area to the fluid pressure in the brake cylinderand upon the opposite side or other area to that in the train pipe. Tothis end the valve shell 1 is formed with a passage or bypass F, openingat one end into the train pipe passage 5, above the double check valve13, and at its other end communicating with said passage 5 below thecheck valve. The opening and closing of this passage F is controlled bythe smaller end 33, of a differential piston that is mounted toreciprocate in a chamber 31, which is in communication with the brakecylinder passage 3, through a duct 0. The large area 30, of thedifferential piston is thus exposed to the pressure from the brakecylinder, while its smaller area 33 is exposed to that from the trainpipe.

When the parts are in the position shown in Fig. l, the triple valve isin its exhaust or charging position, the brake cylinder being open tothe atmosphere through the ports and passages connecting it with theexhaust port 7, and the pressure in the train pipe having caused thecheck valve 13 to be seated against its upper seat 13 thereby cuttingoff the train pipe passage from the auxiliary reservoir, so that saidpressure is retained in the train pipe; but such pressure at the sametime has acted upon the small area 33 of the differential piston againstbut little pressure on the large area, and has moved said piston to openthe passage F so that the fluid may pass from the train pipe throughsaid passage into the valve chamber 2 and thence to the auxiliaryreservoir to charge the same.

Should the pressure in the train pipe be reduced forastopservice oremergency the triple valve will have been so moved, as in Fig. 2, or asin Fig. 3, that the fluid pressure let into the brake cylinder, eitherfrom the auxiliary reservoir or from the train pipe direct, will actupon the large area 30 of the differential piston and move the same toclose the passage F and prevent the fluid from passing around or pastthe check valve 13 through said passage; and this closing movement ofthe differential piston owing to the difference in the areas of itsopposite ends will be proportionately quickly effected.

In service stops after the first reduction of pressure in the train pipeto effect the movement of the triple valve, as in Fig. 2, no air canleak from the valve chamber 2 or from the auxiliary reservoir into thetrain pipe because of the closing of the passage 5 by the seating of thedouble check valve 13 upon its lower seat 13 and by the closing of thepassage F by the seating of asmall check valve 40, so that whether ornot the pressure in the brake cylinder has been raised enough to movethe differential piston to close the passage F is immaterial, but in theconstruction shown, owing to the large difference in the two areas ofthe differential piston, it will be necessarily moved to close thepassage F when the total pressure on the large area exceeds that on thesmall area.

In bringing the parts of the triple valve to the emergency stopposition, as shown in Fig. 3, the train pipe pressure is reduced to alarger extent than that needed to effect a service stop, and thisresults in causing the double check valve 13 to seat upon its lower seat13 and about simultaneously therewith the ICC - operating piston 15(under the pressure in the the train pipe passage 5 with the brake cy1-inder passage 3 and also bringing the end of the finger 18 immediatelyabove the end 18 of the double check valve. Immediately the train pipepassage is open to the brake cylinder passage, the pressure above thedouble check valve expands through the recess of the valve 8, into thebrake cylinder, thereby permitting the train pipe pressure below thedouble check valve overcoming its weight to raise said valve against theend of the finger 18, which prevents it from seating against its upperseat- 13 and holds the train pipe open so that the pressure from thetrain pipe may expand directly into the brake cylinder. Assoon asthepressure in the train pipe and in the brake cylinder is equalized thedouble check valve falls to its lower seat l3 by gravity, and thepressure in the auxiliary reservoir having also been gradually passinginto the brake cylinder by the coincidence of the ports and 8 and it maybe bythe passage 3, whereby the pressure tending to hold the operatingpiston at the limit of its outward movementhasbeen reduced, the spring17 commences to slowly move said operating piston forward toward itsnormal position so that the end of the finger 18 is removed fromposition to obstruct the seating of the double check valve upon itsupper seat. As soon as the parts have moved to the emergency positionand the pressure in the brake cylinder acting upon the larger area ofthe difierential piston is enough to exceed the train pipe pressureacting upon its smaller area 33, said difierential piston closes theby-passage F so that no pressure can pass in either direction throughsaid bypassage. When the small check valve is used it moves to close theby-passage F immediately the train pipe pressure is reduced to effectthe emergency stop as before explained, and remains seated until thepressure in the brake cylinder has been sufficiently reduced, byexhausting to the atmosphere as hereinafter explained, that the pressurein the train pipe acting upon the smaller area 33 of the differentialpiston is sufficient to overcome the pressure in the brake cylinderthatmay be acting upon the large area 30 of said piston and to causesaid piston to be moved to open the by passage F. After the parts havemoved to emergency position and the pressure has become equalized bothabove and below the valves 10 and 8, the tension of the spring 17 issufficiently strong to start the piston toward its normal position andthus remove the finger 18 from abovethe end of the double check valve13, so that when the train pipe pressure is raised to cause the parts toreturn to release position the double check valve is free to seatagainst its upper seat 13 to confine the pressure to the rear side ofthe operating piston and thus efiect its movement.

When it is desired to release the brakes while the parts are inemergency stop position the pressure in the train pipe is raised,causing the double check valve 13 to belifted against its upper seat 13,to close the train pipe the finger 18 having moved to permit thisseating of the check valve so that no pressure may leak therefrom intothe cylinder 6 or into the brake cylinder, and such pressure passes bythe passage 14 to the rear of the operating piston 15 so that aided bythe spring 17 it causes the piston 15 to move toward its normalposition, first moving the slide valve 10 and thereafter also moving theslide valve 8 so as to bring the parts back to the normal position shownin Fig. 1. When this position is reached the brake cylinder is open tothe atmosphere through the passage 3, the recessof the valve 8,port 8",recess 10", duct 9, and

exhaust port 7, thereby permitting the pressure in the brake cylinder toexpand to the atmosphere and thus release in the brakes. As soon asthisoccurs, or as soon as the pressure in the brake cylinder acting uponthe large area 30 of the differential piston is less than the pressurein the train pipe acting upon the small area 33 of said piston, suchditferential piston will be moved by the train pipe pressure from theposition shown in Fig. 3 to the position shown in Fig. 1, so that if itbe now desired to charge the auxiliary reservoir,

the train pipe pressure may pass around the double check valve 13 by theby passage F and thence by passage 5 and valve chamber 2 into theauxiliary reservoir. From the foregoing it will be noticed that in thusreturning the parts of the triple valve to the release position shown inFig. 1,and opening the brake cylinder to the atmosphereso that thebrakes are released, the only expansion that has taken place of thetrain pipe pressure has been that caused by the return movement of theoperating piston 15 and in effecting this return movement of the pistonpositively. It will also be noticed that as said by passage F remainsclosed until the brake cylinder is substantially exhausted, no pressurehas passed from the train pipe into the valve chamber or into theauxiliary reservoir, or, in fact, into any part of the triple valve infront of the piston 15, so that not only has the train pipe pressurebeen saved and confined to one side of the operating piston, but it hasbeen prevented from passing to the opposite side of the operating pistonto retard its quick return movement, and it is only when and after theparts of the triple valve have assumed the release position shown inFig. 1, and the pressure in the brake cylinder has been exhausted ornearly exhausted, that the by passage F is opened to permit theauxiliary reservoir to be recharged; so that when this is done suchpassage of the pressure to the auxiliary reservoir by the by passage Foccurs only after the train pipe pressure has effected the absolutereturn of the operating piston and its connected valves to said releaseposition. It now it be desired to apply the brakes, as for instance fora servlce stop, the train pipe pressure is reduced suflicient to haverelieved the pressure by the passage 14 upon the rear of the operatmgpiston that the auxiliary reservoir pressure acting against its oppositeside moves said operating piston and valve 10 into the position shown inFig. 2, so that the recess 10 is moved to close the duct 9 and the port10 of said valve 10 is moved into coincidence with the port 8 in thevalve 8 permitting the auxiliary reservoir pressure to pass into thebrake cylinder until such time that such pressure and the pressure inthe train pipe is equalized, whereupon the spring 17, which had beenslightly compressed by the rearward movement of the piston 15, will nowmove said piston and the valve 10 into the position shown by dottedlines in Fig. 2, therebyremovin gtheport10 from coincidence with theport 8 cutting off the auxiliary reservoir pressure from the brakecylinder. As soon as the train pipe pressure is reduced to cause theparts to move to this service stop position as in Fig. 2, the pressurethrough the by passage F' is also consequently reduced so that the smallcheck valve 40 moves to its seat, closes such passage F and thusprevents any pressure from the auxiliary reservoir or the valve chamber2 or in the train pipe passage 5 above the double check valve 13 to leakinto the train pipe. As soon as the pressure in the brake cylinderacting upon the large area 30 of the differential piston is enough toovercome the reduced pressure in the train pipe acting upon the smallarea 33 of said piston the differential piston will move from theposition shown in Fig. 1 to the position shown in Fig. 2, closing the bypassage F so that whenever the train pipe pressure is raised to returnthe parts to the released position again, such pressure in the trainpipe is prevented from leaking into the valve chamber 2 to retard thequick return of the operating piston 15.

If it be desired to recharge the auxiliary reservoir while the brakesare on and the parts are in the position shown in Fig. 2 as modified bythe position indicated by the dotted lines, the train pipe pressure isslightly raised (not sufficient to hold the double check valve 13 to itsupper seat), so that such pressure flows past said double check valveinto the valve chamber 2 and thence into the auxiliary reservoir. Thisrecharging is effected without disturbing the position of thedifferential piston shown in Fig. 2, closing the by passage F.

I From the foregoing it will be understood that a very efficient meansis provided for insuring a positive release of the brakes and effectingan important saving of the fluid pressure, as well as enabling themaintaining of pressure in the long length of. train pipe incident to along train of cars, while the pressure is being simultaneously relievedfrom all of the brake cylinders in the train.

The proportion of the areas, 30, 33, of the difierential piston will begoverned by the pressures under which the triple-valve operates, butassuming it capable of operating upon a reduction of twenty poundspressure in the train pipe from a normal pressure-of seventy pounds, thelarge area of the differential piston is preferably six times greaterthan the small area; in which case the said piston will continue toclose the passage F upon the release of the brakes until the pressure inthe brake cylinder has been lowered to a little more than one-sixth ofthat in the train pipe when the much greater pressure acting upon thesmall area will cause the piston to move to open said passage.

To prevent any escape of the pressure in the reverse direction throughthe passage F, such passage is provided with the small check valve 40adapted to close said passage the moment the pressure shall drop in thetrain pipe, as before explained.

It is to be understood that the use of the passage or bypass anddifferential piston and the check valve 40 is not confined to theparticular form of so called triple valve shown and set forth herein,but that it may be used in other forms of triple valves; and thatinstead of using a difierential piston for controlling the admission ofthe fluid pressure to the auxiliary reservoir when releasing the brakes,it may be employed to open and close communication between the trainpipe and brake cylinder in another form of triple valve, arranging andproportioning the piston so that a reduction of pressure in the trainpipe as for instance for an emergency stop of twenty pounds will causeit to move to open the train pipe into communication with the brakecylinder. Thus in applying the improvement to the form oftriple valverepresented in Fig. 4, substantially the same construction may beemployed, the only changes that are necessary being the addition of aflange 4: on the end of the exhaust valve l to close communicationbetween the train pipe and the auxiliary reservoir except when saidvalve is in exhaust position; and the closing of the direct chargingport F The by pass F opens into the passage G that is in communicationwith the auxiliary reservoir and into the train pipe passage A, throughthe opening F; the smaller area 33 of the differential pistoncontrolling the communication of the train pipe passage with theauxiliary reservoir by closing the pass F, while the larger area 30 ofthe differential piston is open by the passage 0 to the brake cylinder.The action of this differential piston is the same as before describedand need not be repeated here.

What is claimed is 1. In a fluid pressure brake, the combination of avalve controlling the exhaust from the brake cylinder, a fluid pressuresupply passage communicating with a reservoir, and a second valvecontrolling said passage the movement of which is effected by thevariations of pressure in the brake cylinder, substantially asdescribed.

2. In an air brake apparatus, the combination with the triple valve, ofanother valve exposed tothe brake cylinder pressure and closingcommunication between the train pipe and auxiliary reservoir while thebrakes are on, substantially as described.

3. The combination with the triple valve of an air brake apparatuscontrolling the passage of pressure to the brake cylinder of anothervalve controlling communication between the train pipe and auxiliaryreservoir and exposed to the brake cylinder pressure, and a check valvein the train pipe to hold the pressure in auxiliary reservoir,substantially as described.

4. The combination with a brake cylinder, reservoir, triple valve andtrain pipe, of a passage connected with the train pipe and leading to areservoir forming a portion of the air brake apparatus, and adifferential pistion or valve controlling said passage exposed to thechange in pressures in the train pipe and brake cylinder to open orclose said passage after the movement of the triple valve, substantiallyas described.

5. The combination with a brake cylinder, reservoir, triple valve andtrain pipe, of a passage leading from the train pipe and communicatingwith the auxiliary reservoir, and a difierential piston or valvecontrolling said passage, the difierential areas of which are exposedboth to the brake cylinder and to the train pipe pressures to open andclose said passage after the triple valve has moved, substantially asdescribed.

6. The combination with a brake cylinder, reservoir, valve, train pipeand a check valve in said train pipe, of a by passage extending from thetrain pipe to the upper side of said check valve, and a piston or valveautomatically controlling said by passage, substantially as described.

'7. The combination with a brake cylinder, reservoir, triple valve,train pipe and a dou-' ble seated check valve in said train pipe, of aby passage opening into the train pipe upon opposite sides of saiddouble check valve and a piston or valve controlling said by passageexposed to the train pipe and to the brake cylinder pressu res,substantially as described.

8. The combination with a brake cylinder, reservoir, triple valve andtrain pipe, of a by passage leading from the train pipe andcommunicating with the reservoir, a check valve closing one end of saidby passage and a piston or valve controlling the other end and exposedto the brake cylinder and train pipe pressures, substantially asdescribed.

9. The combination with a brake cylinder, reservoir, and valve forcontrolling the admission and exhaust of fluid-to and from the brakecylinder, of a supply passage communicating with the auxiliary reservoirand a piston or valve controlling said passage and an air passageconnection between the said piston or valve and the brake cylinderwhereby the piston or valve is operated by an increase and decrease inpressure in the brake cylinder, substantially as described.

10. The combination in an air brake apparatus, of a train pipe passageto theauxiliary reservoir, a by pass from the train pipe passagecommunicating with the auxiliary reservoir having a valve exposed to andmoved to open said by pass by the train pipe pressure when the brake isreleased, substantially as described.

11. The combination, in an air brake apparatus, of a check valve in thetrain pipe passage adapted to close the same on an increase of pressurein the train pipe, and a by pass around or past said check-valve havinga valve moved to open said by pass by the train pipe pressure when thebrake is released, substantially as described.

12. The combination, in an air brake apparatus, of a check valve in thetrain pipe passage, a connection with the triple valve adapted in onepositiou to hold the check valve from its seat, a by pass around or pastsaid check valve and a piston or valve controlling said by pass moved toopen the by pass after the triple valve is in release position,substantially as described.

In testimony whereof I have hereunto set my hand, this 4th day of May,A. D. 1892, in presence of two witnesses.

HENRY L. HOWE.

Witnesses:

MAX 0. BEARD, HENRY STEWART.

